The present invention relates to a method for producing a grinding agent carrier comprised of a carrier body and a layer of grinding agent on the surface of the carrier body.
Grinding agent carriers, in the form of a plastic grinding foil as a carrier body having an embedded grinding agent uniformly distributed over its surface and pressed thereinto, have been used to grind cutting styli and pickups for information carriers. Grinding foils, a method for profile grinding a mechanical signal scanner, and a device for practicing the grinding process are all disclosed in German Offenlegungsschrift No. 2,053,866. To practice this profile grinding method, a flexible plastic foil is used which should have a thickness, for example, of about 100.mu. and whose surface contains grooves with a certain profile which corresponds to the desired shape of the pickup to be ground and a grinding agent finely distributed and embedded in its surface, for example, diamond powder.
Grinding foils are also used in the profile-free grinding of cutting styli which are used to cut modulated signal grooves into lacquer foil as preliminary stages for video or audio records. The grinding foils for use in profile-free grinding are flexible plastic grinding discs having a planar, unprofiled surface which is also provided with an embedded grinding agent.
As has been found in practice, the grinding foils for the intended purpose must meet considerable requirements, particularly with respect to uniformity of distribution of the grinding agent embedded in the surface of the grinding foil. The uniformity of the grinding agent layer is of particular significance if a grinding agent carrier is to be produced which is to have only a single layer of grinding agent as disclosed, for example, in German Offenlegungsschrift No. 23 50 732.
In German Offenlegungsschrift No. 23 12 149, which is hereby incorporated by reference, there is disclosed a method for producing a grinding agent carrier including a carrier body which is provided on its surface with a layer of grinding agent, such as diamond powder, by forming the layer of grinding agent on a planar substrate by sedimentation from a grinding agent suspension and then transferring the so-formed layer from the planar substrate and bonding it to the carrier body. In one embodiment of the method disclosed in German Offenlegungsschrift No. 23 12 149, the grinding agent layer is applied directly by sedimentation onto the carrier body as the planar substrate so that a transfer from the otherwise employed auxiliary substrate to the carrier body to be coated is eliminated. In the method disclosed in German Offenlegungsschrift No. 23 12 149, the edges of the planar substrate are provided with edge limitation means to prevent the suspension from running off the planar substrate, but the use of such edge limitation means can lead to inhomogeneities in the edge zone of the grinding agent layer. Further, in the method in German Offenlegungsschrift No. 23 12 149, after the suspension is applied to the planar substrate, the suspending medium is removed by such means as sucking away, siphoning off, or by evaporation, and the transfer of the grinding agent layer to the carrier body is done by the use of a press heated to temperatures in the range of, for example, 150 to 170.degree. C.